    (fn [chapters]
      (-> chapters
          (update (-> index (rest) (rest) (first)) updater)))))
+
+;; -------- Content loading -----------
 
 (defn load-if-not-exist
   ([getter load-fn on-loaded]

(defn set-active-serial [serial-id active-content-index]
  (assoc active-content-index 0 serial-id))

;; TODO: think about lenses

(defn save-apply [& args]

      (-> db
          (assoc :seasons-list saved-seasons)
          (assoc :chapters-list saved-chapters)))))
;; TODO: what is it???
(register-handler
  :save-seasons-and-chapters
  (fn [db _]
